Why $CH_3OH$ is more acidic than $H_2O$ while the same is opposite for other alcohols?
Asked
Active
Viewed 528 times
-1
-
https://chemistry.stackexchange.com/questions/57986/is-methanol-really-more-acidic-than-water – Mithoron Jan 25 '19 at 17:40
2 Answers
2
The question is based on the assumption, that water has a pKa of 15.7 which is usally not correct.
As a paper mentioned in this thread What is the Real Pka of WATER the pKa of water in water should be 14.It might be different when water is a reactend in organic solvents, for that the paper mentioned by the thread author is helpful.
Inselino
- 419
- 3
- 9
0
Like other alcohols Methanol is also a weaker acid than water; sodium methoxide undergo easy hydrolysis with water forming methanol and sodium hydroxide, the equilibrium being more in favour of the products. Since methoxide ion is a stronger base than hydroxide the parent acid methanol must be weaker acid than water $\ce{CH3O^-Na^+ + HOH<=>CH3OH + Na^+OH^-}$
Nandakumar U K
- 181
- 1
- 12